<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
</head>
<body>
<header></header>
<div id="app">
  {{message + 1}}
  <br>
  {{ 1 + 1 }}
  <br>
  {{ true ? 1 : 0 }}
  <br>
  {{ ++i }}
</div>
<footer></footer>
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
<script>
  (function () {
    var i = 0;
    new Vue({
      el: '#app',
      data: {
        i: 0,
        message: 'Hello World 2'
      }
    })
  })()
</script>
</body>
</html>
